George iiowlett dayis



Nomen G. H. DAVIS.

DUPLIGATING APPARATUS. No. 404,778. Patented June 4, 1889.

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` 7 QUNTTED STATES PATENT OFFICE.'

GEORGE I'IOYLETT DAVIS, OF IVASHINGTON, DISTRICT OF COLUMBIA, v ASSIGNOR TO AUGUSTUS D. KLABER, OF NEV YORK, N. Y.

DUPLICATING APPARATUS.

SPECIFICATION forming part of Letters Patent N o. 404,778, dated June 4, 1889. Application tiled April 18, 1888. Serial No. 271,012. (No model.) Patented in England November 20, 1888, No. 17,140.

To all whom t may concern:

Be it known that I, GEORGE HOWLETT DA- vIs, a citizen of the United States, residing at Vashington, in the District of Columbia, have invented certain new and useful Improvements in Duplicating Apparatus, of which the followingis a specification.

My invention relates to that class of duplicating apparatus which employs a printingstencil over which an inked roller is passed, and has for its object to provide an inexpensive and practical device for automatically delivering the sheets after they have been printed.

In the accompanying drawings, Figure 1 shows a duplicating apparatus elevated on a box with the stencil-frame closed, and the manner of passing a roller over the printingstencil to print the sheet laid underneath it. Fig. 2 shows the same apparatus with the printing-frame opened. Fig. 3 shows a transverse sectional view of the apparatus with the stencil-frame closed. Fig. 4 is a similar sectional view showing the stencil frame opened.

Similar letters refer to like parts throughout the several views.

A is a stencil-frame with the inner side A rounded, and is hinged to the printing-board B in the manner shown. The said printingboard B is cut outbetween the hinges, so that when the said stencil-frame is raised there will be a mouth or an enlarged longitudinal opening B between their hinged sides.

The printing-stencil C is shown with two small air-holes C made through it near the corners of the printing-frame next the hinges.

The operation of myinvention is as follows: First, before commencing to print slightly curl one side of the pile of paper to be printed, so that each sheet when placed on the printing-board presents a concave surface or groove to the stencil. The curled side of the sheet should be farthest from the hinges. A sheet to be printed is placed on the printing-board and the stencil-frame closed. After the roller has been` passed over the printing-stencil the stencil-frame is raised rapidly. Owing to adhesion and suction the printed sheet rises part way with the printing-stencil until its own weight, assisted by air coming through the air-holes, detaches it from the stencil, whereupon it drops in a slanting direction through the mouth onto the table beneath, an obstruction being placed at a convenient distance on the table, so as to stop the sheets and cause them to drop one on top of another as fast as they arel printed. rlhe inner side A of the stencil-frame is rounded olf, so as to slide the lower edge of the detached sheet into the mouth in case it should strike the said side in dropping.

In somel cases it is not essential to make air-holes through the printing-stencil, as the Weight of the sheet alone is sometimes sufficient to cause it to drop from the stencil at the proper time; but the air-holes are necessary when the sheets adhere to the stencil too long.V

It is obvious that my invention can be applied to all classes or constructions of duplicating apparatus employing a printing-stencil by making a mouth of sufficient size in such a position that when the sheet drops from the stencil it will fall through the mouth, substantially as described. In some duplicating apparatus the printing-stencil is level with the under edge of the stencil-frame, in which case my improvements are better adapted, as the sheets in dropping from the stencil do not come in contact with the side of the frame; but I prefer to show my improvements in connection with a standard duplicating apparatus by slightly changing its construction.

The method herein disclosed of discharging a printed sheet from a duplicating apparatus, which consists in raising the stencil-frame with sufficient rapidity to create a suction of air or vacuum, whereby the printed sheet is lifted above the printing-board, and in providing a suitable opening for the sheet to fall through, is claimed by me in another application filed March 7, 1889, Serial No. 302,322, and I therefore in this application claim only the novel features of construction (and not the method) as herein disclosed.

What I therefore claim as new, and desire to secure by Letters Patent, is-

l. In a duplicating apparatus, a printing- IOO stencil with one or more air holes made therein for releasing a sheet adhering to the said stencil, substantially as described.

2. In a duplicating apparatus,the combination, with a stencil-frame, of a printing-board constructed with an inclined surface at its hinged side and cut away between the hinges, so as to leave a longitudinal opening, substantially as and for the purposes described.

3. In a duplicating apparatus,the combination of a stencil-frame the inner side A of which is rounded oi, and a printing-board constructed with an inclined surface at its hinged side and cut away between the hinges, so as to leave a longitudinal opening, substantially as and for the purposes described. In testimony whereof I aiiix my signature in presence of two witnesses.

G. HOWLETT DAVIS. lVitnesses:

L. S. ANDERSON, F. L. OURAND. 

